The 49ers placed Okuayinonu (foot) on injured reserve Friday.
Okuayinonu was already ruled out for Week 1 against the Rams due to a foot injury, which is severe enough for him to go on injured reserve. That means he'll be required to miss at least four games (barring an injury settlement), so the earliest Okuayinonu can return is Week 5 against the Seahawks on Sunday, Oct. 11. In a corresponding move, the 49ers signed edge rusher Khalid Kareem from the Falcons' practice squad to the active roster.